package com.itheima;

import java.util.HashMap;
import java.util.Map;
import java.util.Set;
import java.util.function.BiConsumer;

public class MapDemo {
    public static void main(String[] args){
        test3();

    }

    public static void test3() {
        Map<String,Double> map = new HashMap<>();
        map.put("张三",90.0);
        map.put("李四",80.0);
        map.put("王五",100.0);
        map.put("赵六",60.0);

        /*map.forEach(new BiConsumer<String, Double>() {
            @Override
            public void accept(String key, Double value) {
                System.out.println(key + "---" + value);
            }
        });*/
        map.forEach((key,value) -> System.out.println(key + "---" + value));
    }

    public static void test2() {
        Map<String,Double> map = new HashMap<>();
        map.put("张三",90.0);
        map.put("王五",100.0);
        map.put("赵六",60.0);
        map.put("李四",80.0);
        //1.将map集合转换成set集合(将map中的key-value绑定成一个对象entry)
        Set<Map.Entry<String,Double>> entrySet = map.entrySet();
        //2.遍历set集合
        for (Map.Entry<String,Double> entry : entrySet){
            //3.根据entry获取key和value
            String key = entry.getKey();
            Double value = entry.getValue();
            System.out.println(key + "---" + value);
        }
    }

    public static void test1() {
        Map<String,Double> map = new HashMap<>();
        map.put("张三",90.0);
        map.put("李四",80.0);
        map.put("王五",100.0);
        map.put("赵六",60.0);
        Set<String> keySet = map.keySet();
        for (String key : keySet){

            Double  value = map.get(key);
            System.out.println(key + "---" + value);
        }
    }
    private static void test0() {
        Map<String,Double> map = new HashMap<>();
        map.put("张三",90.0);
        map.put("李四",80.0);
        map.put("王五",100.0);
        map.put("赵六",60.0);
        map.put("王五",90.0);
        System.out.println(map);

        map.remove("张三");
        System.out.println(map);

        boolean  b1 = map.containsKey("李四");
        System.out.println(b1);
        boolean  b2 = map.containsValue(90.0);
        System.out.println(b2);
        //map.clear();
        //System.out.println(map);

        boolean empty = map.isEmpty();
        System.out.println("empty"+ empty);
        int size = map.size();
        System.out.println("size"+ size);
    }
}
